{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"e5f1bfa1ba48000b80bfdc44da2ede973891ecf3adbf8ef80c399e0431ad404d","created":"2026-10-15T23:43:22Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["ce59fb6cd812fc05906d0c60a71c75ea22bc686bcf38e7c3ef7010834d98ee7b","f50a75152339e28336a55824c774f0efcd2d2f1cf1a8f8960703be6182972062"],"salt":"ab4b2a6e3184baf8f362e96c01e66725d72557ae63c3f01a7a8ba6e3d25c2259","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"identification","assisted_by":[],"external_id":"cm.phonon-thermal-hall.intrinsic-or-defect","kind":"well-posed","literature_status":"open","n":"2","parents":[],"plain":"The effect could come from the phonons themselves or from the way they scatter off impurities. $\\mathrm{SrTiO_3}$, where it is large, is a clean place to decide.","posed_since":"","precise":"For $\\mathrm{SrTiO_3}$ with $\\kappa_{xy}/\\kappa_{xx}$ up to $\\sim 3 \\times 10^{-3}$ at $9 \\times 10^{4}\\,\\mathrm{G}$ near the $\\kappa_{xx}$ maximum, determine whether $\\kappa_{xy}$ arises from band-intrinsic phonon chirality (for example involving the soft polar mode and structural domains) or from extrinsic skew scattering, by establishing how $\\kappa_{xy}$ scales with $\\kappa_{xx}$ and with controlled defect density (oxygen vacancies, isotope substitution).","problem_ref":"f50a75152339e28336a55824c774f0efcd2d2f1cf1a8f8960703be6182972062","references":"","settled_by":"$\\kappa_{xy}$ measured on crystals with independently quantified defect density, combined with first-principles phonon Berry curvature for $\\mathrm{SrTiO_3}$.","status_note":"In $\\mathrm{SrTiO_3}$ disorder and strain suppress $\\kappa_{xy}$ and annealing partly restores it without changing $\\kappa_{xx}$ (Xiang et al., npj Quantum Materials 11, 40, 2026, arXiv 2511.08932); the authors read this as an intrinsic lattice effect sensitive to imperfections, not yet tied to a microscopic mechanism.","title":"Intrinsic versus defect-driven phonon thermal Hall effect in $\\mathrm{SrTiO_3}$","topic_ref":null},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"45ba10864d64f7c9bd954333e74e8c05a1b01a308c5e385714e62d778c4d7c22","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"8e8089adba7f17dfaa8a30a6498cdd0bf072db94ee23b45ca4f0c499630f3699","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"-OU4dTLG3F-rssyLfO6nznbYutBie-ZZDuiQaCtDcr78AWOoQkZxoEgjXDc1S0D4oQX_fJBzw0UZmhPkChRWDQ"},"schema":"pubphys.envelope/1"},"record_hash":"45ba10864d64f7c9bd954333e74e8c05a1b01a308c5e385714e62d778c4d7c22","leaf_index":2992}